Gas absorption, separation and recovery processes have long been provided for both industrial and environmental purposes. Industrial applications typically involve processes for separation and removal of at least one gaseous component from a process gas stream in order to enhance the quality of gas products produced and/or to prevent undesirable downstream operational problems that might subsequently occur in downstream processes. Examples are the removals of carbon dioxide (CO2) and/or hydrogen sulfide (H2S) from natural gas and synthesis gas, and the removals and separations of volatile organic compounds (VOCs) and gases such as nitrogen (N2), oxygen (O2) and hydrogen (H2) from industrial process gas streams. Environmental applications typically involve the removal of at least one gaseous component such as sulfur dioxide (SO2), CO2, oxides of nitrogen (NOx), and mercury (Hg) from combustion flue gases or exhaust gas streams in order to reduce emissions of air pollutants to the atmosphere.
Large-scale combustion processes are commonly used for municipal and industrial energy production, in the manufacturing of refined products from raw ores and other crude materials, and for the disposal of municipal and industrial waste materials. Such combustion processes typically produce on a continuous basis, large volumes of gaseous exhaust waste streams that contain one or more highly undesirable gaseous compounds such as CO2, H2S and NOx among others, which cause significant environmental pollution and health risks. In particular, persistently increasing atmospheric concentrations of CO2 arising from large-scale continuous municipal and industrial combustion are the primary cause of global warming which is responsible for increasing trends in the incidences of environmental perturbations and pollution-associated health problems.
Despite their widespread use, industrial gas absorption processes currently in use present economic shortcomings due to significant energy requirements for regeneration of solvents used for absorbing selected gases from the process or exhaust gas streams. This causes an impediment for industry to reduce the energy and process costs, and to meet their environmental performance targets.